com.sample.MyGroceryListServlet.java Source code

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Here is the source code for com.sample.MyGroceryListServlet.java

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/*
 * Licensed Material - Property of IBM
 * (C) Copyright IBM Corp. 2014 - All Rights Reserved.
 * US Government Users Restricted Rights - Use, duplication or disclosure
 * restricted by GSA ADP Schedule Contract with IBM Corp.
 */
package com.sample;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.Mongo;
import com.mongodb.util.JSON;

/**
 * Servlet implementation class MyGroceryListServlet
 */
@WebServlet("/MyGroceryList")
public class MyGroceryListServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    private static final String[] myGroceryList = new String[] { "Milk", "Bananna", "Apple", "Cereal", "Potato" };

    /**
     * @see HttpServlet#HttpServlet()
     */
    public MyGroceryListServlet() {
        super();
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // Reference: http://docs.mongodb.org/ecosystem/tutorial/getting-started-with-java-driver/#getting-started-with-java-driver

        String envVars = System.getenv("VCAP_SERVICES");

        DBObject dbO = (DBObject) JSON.parse(envVars);
        String parsedString = dbO.get("mongodb").toString();

        // Remove trailing and starting array brackets (otherwise it won't be valid JSON)
        parsedString = parsedString.replaceFirst("\\[ ", "");
        parsedString = parsedString.replaceFirst("\\]$", "");

        // Get the credentials
        dbO = (DBObject) JSON.parse(parsedString);
        parsedString = dbO.get("credentials").toString();

        // For debugging only
        // System.out.println(parsedString);

        dbO = (DBObject) JSON.parse(parsedString);

        System.out.println("Host name : " + dbO.get("hostname"));
        String hostName = dbO.get("hostname").toString();
        int port = Integer.parseInt(dbO.get("port").toString());
        String dbName = dbO.get("db").toString();
        String userName = dbO.get("username").toString();
        String password = dbO.get("password").toString();

        Mongo mongoClient = new Mongo(hostName, port);

        DB db = mongoClient.getDB(dbName);
        db.authenticate(userName, password.toCharArray());

        // Clean up old entries
        DBCollection coll = db.getCollection("testCollection");
        coll.drop();

        BasicDBObject lastAddedObject = null;
        for (String curItem : myGroceryList) {
            lastAddedObject = new BasicDBObject("i", curItem);
            coll.insert(lastAddedObject);
        }
        response.getWriter().println("<b>My grocery list is:</b>");

        coll.remove(lastAddedObject);
        DBCollection loadedCollection = db.getCollection("testCollection");
        DBCursor cursor = loadedCollection.find();
        try {
            response.getWriter().println("<ul>");
            while (cursor.hasNext()) {
                response.getWriter().println("<li>" + cursor.next().get("i") + "</li>");
            }
            response.getWriter().println("</ul>");
        } finally {
            cursor.close();
        }
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // TODO Auto-generated method stub
    }

}